Species Population Trends for Great Britain

Summary of species trends for Great Britain

This page provides a summary of the population trends at GB-level for species monitored by the NBMP. For a summary of the results of the country-level trends for England, Scotland and Wales, click here.

The table below shows the smoothed population indices derived from NBMP data in Great Britain to the end of 2016. For each species, the number of sites contributing to the 2016 trend calculations is shown as well as an approximation of the average annual percentage change in the index since the baseline year. It should be noted, however, that the average annual percentage change makes assumptions about the data analysis, and is only genuinely appropriate for those species for which the trend line appears to be linear.

Click on the species names in the following table to access information on:

The species population trends for GB and information at country or regional level where data are available

1For brown long-eared bat the Hibernation Survey shows a marginally significant decline in the most recent year when compared to the baseline year. Given the provisional nature of estimates for the most recent year, the small margin of significance and the fact that this margin is likely to change when additional years of monitoring data are added to the trend, there is not yet sufficient certainty to assess the population as declining.

Trends in context:

These trends reflect relatively recent changes to bat populations since the 1990s. It is generally considered that prior to this there were significant historical declines in bat populations dating back to at least the start of the 20th century, although evidence is fragmented and few data were collected in a systematic way.

Information about the factors that affect our bat populations can be found here